Field of the Invention
The present invention relates generally to the field of displays for measurement instrumentation. More specifically, the present invention discloses a measurement instrument having a rolling display in which the large dynamic range of sensor readings is displayed using a relatively small array of display elements.
Statement of the Problem
A wide variety of measurement instrumentation have been known for measuring and detecting a physical phenomenon, and providing a visible display for the user in response. For the purposes of this disclosure, the term “measurement instrumentation” should be broadly construed to include any type of instrumentation, detector, sensor, or other device for measuring a physical phenomenon over a very large dynamic range. Ultrasonic leak detectors (ULDs) are one example of such measurement instrumentation. They are often required to span a dynamic range of signal intensity of 120 dB or more.
In addition, measurement instruments are commonly designed to be portable or handheld for convenient use in the field. This creates practical limits on the size and resolution of the display that could be carried by the device. Thus, a large dynamic range is difficult to display in a limited-size display, such as a bar graph.
3. Solution to the Problem
To address these shortcomings in the prior art, the present invention provides a measurement instrument (e.g., an ultrasonic leak detector) having a rolling display that enables a large dynamic range of sensor readings to be displayed using a relatively small array of display elements. In particular, the present invention divides the dynamic range of the device into a plurality of sub-ranges (i.e., N sub-ranges). Sensor readings in the first sub-range are displayed using one display element at a time in the array. Sensor readings in the second sub-range are displayed using two display elements at a time in the array, and sensor readings in the Nth sub-range are displayed using N display elements at a time in the array.